I have been using the 14$ Shareware Cache Killer II for the last 4 years, all this time never having to worry about emptying my browsers caches. I put an alias of it in my System's Shutdown folder, thus always starting with empty caches when booting. Instead, one can put the alias in the Startup folder to do emptying at startup.
The app searches for Cache folders in any installed browser and lists them in a Preference document in the System's Preferences folder. You can manually remove any listed folder. As well you can add any other folder(s), Cache or not, and have them emptied. Why one would list a folder that is not a Cache folder, I don't know and can't think of any reason to do so, but it can be done.
jb